Adjustable portable lamp



FIG. 1 is a left side elevational view showing my new design for an adjustable portable lamp;

FIG. 2 is a top plan view;

FIG. 3 is a front elevational view;

FIG. 4 is a rear elevational view; and

FIG. 5 is a bottom plan view thereof.

The broken lines are shown in FIG. 1 for illustrative purposes only. 

The ornamental design for an adjustable portable lamp, as shown and described. 